1. Field of the Invention
The present invention relates to equipment for manufacturing surgical equipment, and more particularly to an apparatus for constructing surgical suture-needle assemblies which secures the suture to the needle shank to form the suture-needle assembly.
2. Discussion of the Prior Art
In the suture field, and in particular the suture-needle assembly industry, there are many known ways of attaching a suture to the needle to form the final surgical assembly. In this field, where the demand for suture-needle assemblies (hereinafter suture-needle assemblies will be referred to as simply "sutures") is ever increasing, the requirement for an efficient, high volume means for assembling sutures is a priority for suture manufacturers. In the prior art, devices for assembling sutures are varied depending on the construction of the needles to which the suture thread is attached.
Typically, many needles are provided with a pointed tip and a blunt shank end which generally includes a longitudinally directed bore hole for accepting therein a suture thread. After the thread is inserted into the bore hole, the shank is crimped or swaged about the thread to hold it in place. Other means of securing the thread within the bore of the needle shank include the use of adhesives or bonding agents to anchor the thread.
It has now become common to secure the thread to the needle shank in such a way so as to allow for the removal of the needle from the thread after the suturing operation is complete. In this manner, a sharp tug or pull on the needle separates the needle from the thread to eliminate the necessity for the surgeon to cut the thread after the suturing procedure is finished. In order to accomplish this, it has become known to apply the thread to the needle shank through the provision of a heat shrinkable tubing which is shrunk about both the shank end and the thread to hold the thread to the needle. After the suturing procedure is complete, the surgeon can then apply a sharp pull force to the needle which separates the thread from the needle by releasing the thread at the heat shrink tubing.
Due to the large volume of sutures manufactured to satisfy the demand in the field, it is necessary to provide an apparatus for assembling the sutures which is efficient and which can handle a high volume under strict quality control. In addition, it is necessary in many cases to protect the suture thread from degradation due to the heat which is applied to shrink the heat shrinkable tubing about the shank and the end of the suture thread. Many types of suture threads, in particular catgut, collagen, and many plastics such as polypropylene, will seriously degrade if the application of heat is prolonged or is applied at excessive temperatures. If the suture thread drys out, it may crack at the connection point, thus rendering the suture useless. On the other hand, inefficient heating will cause ineffective shrinking, thus rendering the connection weak and impractical.
The novel apparatus for securing suture threads to needle shanks to form suture-needle assemblies of the present invention obviates the disadvantages encountered in the prior art and provides an efficient means for constructing sutures at a high volume and with high quality control. The device of the present invention insures a connection between a needle shank and a suture thread which is of high integrity and which protects delicate suture threads from degradation during the securement process. Furthermore, the present invention allows for a high volume and efficient manufacturing process to meet the growing demand for sutures having a quick release feature.